Self-propelled vehicle



July 1, 1947. A. s. sToKl-:s

l SELF-PROPELLED VEHICLE 3 Sheets-Sheet l FiledSept. 18, 1944 A lvorneyb A. s. sToKEs 2,423,266

SELF-PROPELLED VEHICLE Filed Sept. 18, 1944- 3 Sheets-Sheet 2 III llHrllIm Mmmm.-

July 1, 1947.

July 1, 1947. A. s. sToKEs 2 2,423,266

SELF- PROKPELLED VEAHI CLE Filed Sept. 18, 1944 5 Sheets-Sheet 3igea-4Q. uw

A Hor/ley Patented July 1, 1947 p SELF-PROPELLED vineiroLE'V AntonyScott Stokes,` Ipswich, England, assignor` i` to Ransomes & RapierLimited, Ipswich, England, a company of Great Britain Applicationseptember is, 1`944,seria1No. 554,701l

In Great Britain July 20, 1943 i y 5 Claims. (Cl. 180-42) This inventionrelates to self-propelled vehicles of the kind supported upon a pair ofsteered wheels at each end so that there is a. wheel at or near eachcorner of an approximately rectangular chassis. Y

The object of the invention is to provide satisfactory mansforltransmitting drive to the road wheels so that the steering gear willalways operate in the desired manner and a differential gear will not berequired. Y The invention is particularly applicable to trolleys such,for example, as those whichcarry mobile cranes which the post of thesteering wheel for -theA time being nearer the centre of any curvedescribed .by the trolley, will be turned through a -greater angle thanthe associated or outer steering wheel of the same pair. In particularthe inventionis intended for use with such trolleys in which both thefront and rear wheels are arranged to turn about their steering posts sothat a full turning lock is obtained imposed by the use of theso-calledAckerma-n link rods.

According to this invention the trolley com'- prises a substantiallyrectangular frame, 'platm form or chassis supported at each end upon apair of steered road wheels, a single driving unit, a positive drivingconnection betweenthis unit and the front and rear wheels on one `sideof the chassis such that these two wheels are driven at the same speed,`an operative connection for irnparting the appropriate steering movementof the wheel at one end of the trolley to its associated wheel at thesameend, and a driving connection between this associated wheel and thecor? ley i 'I'hus without providing a differential gear or duplicatingthe mechanism which fulfils the function of the steering link rod, thefront rear wheels on any one side of the trolley are always constrainedto move at the same speed and to be turned for steering ypurposes to thesame angular extent.

The particular mechanism used to transmit the drive to the two drivenwheels and to transmit the steering movement may be varied.` Thus asingle power unit mounted between the front and rear axles may drive apropeller shaft extending parallel to the length of the chassis andgeared to vertical driving shafts enclosed in tubular supports about theaxes in which the steered road wheels turn.

The tubular supports of the steered road wheels may each carry asteering worm wheel or segment actuated by worms on a shaft extendingparallel to the length of the chassis and one of these steeredroadwheels, for example the front wheel, is connected through suitablegearing, which in itself forms no part of the present inunrestricted by'the limitations responding wheel at the opposite end of the trolyOFFIQET,

vention,` `to its associated wheel at the end A ofthe vehicle so thatwhicheverrwheel is for-the time being nearer the scribed by the trolley,angle than the other centre of `any curve deis turned through a greaterAwheeL;

The wheel at the opposite end of the vehicle, for example at the rearendof the vehicle `which is not directly steered by the worm isconnected to the mechanism Aabove describedv corresponding wheel on Athesame side ofthe chassis butat the other erich` thereof by means of ropegearing, bevel pinion or other driving connection.

A trolley according designed to carry a crane constructed in the form ofa to the invention= may. hber but it may also be works vtrolley orrtruckwhich can be easily manoeuvred.- `In suchV a case a a seat for thedriver or operator 4is conveniently arranged at a lower level thanthe-platformrof theftruck at one end of `hereafter as the rear end.` i yas appliedto awor-ks truck` or One construction the vehicle but referred-to trolley is illustrated somewhat diagrammatlcally by way of`examplein ings, in which -Figure 1 is a plan,

theaccompanying draw- Figure 2 `is a side elevation.` 1.. Figure3is anend elevatiomand i Figure 4 is a similar view to -Figure 3,...b utin-,section ina plane containing the pivoted axesof the twoadjacentwheels. lThe trolley illustrated comprises a substantially rectangular chassis Ahaving af flat y load?. f

supporting platform B and asteered wheel at each l corner. About midwayin the lengthof the frame" and'on the under side of the platformis apower a unit comprising an in ternal. combustion engine C provided witha normal `clutch and changer speed gearhoused in a gear boxV C1 andprovided with a flexible coupling C2 by whlchitz-is con, nectedto atransversely extending Vdriving'ishaftw C3.j The driving shaftisconnected toa verf. tical transmission shaft D throughlwormgearing andthe upper end of t pinion D1 horizont ally'v extending Y at each end ofthis horizontal pinions F1 lower ends on vertical p spectively at thechassis. l

yoke J which can rotat F and the yokes carry meshing with a drivenhe'shaft D c arriesa .bevel` pinion E1 on a Bevel pi-nionsEg shaft meshwith osts F which carry atftheir shaft El pinions F2 meshing-withAbevelpinions i H on Ythe axles ofthe road wheels G and G1 tre-F fron-tand rear ends of.` the,

is carried, in .at` eabout the vertical shafts lworm segments J4 meshingwith worms Kl-on the ends of a steering shaft K. This shaft can andchain gearK2 the driver. The worm shaft K is wound in th be rotatedthrough a. sprocket by a steering Wheel K3 at Vthe rear end "ofthevehicle adjacent to a* seat" L for f K1 at the front end of the eopposite direction to the the rear end so that when the steering wheelK3 is rotated, the front and rear wheels G, G1 are turned about theirsteering posts in opposite directions.

The angular movements of the front wheel G are transmitted to theassociated front wheel M corresponding worm at through belt-connectedcam mechanism indicated in Figures 1 and 3 which in itself forms no partof the present invention. This cam mechanism is so arranged that bothwheels can have an unrestricted turning movement while the wheel nearerthe centre of any curve being described by the chassis is turned througha greater angle than the other or outer wheel. In the exampleillustrated an elliptical cam N on the tubular support of the yoke J isconnected to an intermediate cam N1V by belting andthe movements of thecam N1 are transmitted by a toothed pinion N2 through an idle pinion Oto a pinion P which vcarries a cam P1 similar to the cam N1. The cam P1is connected by belting to an elliptical cam P2 on the tubular supportM1 of the yoke which supports the front Wheel M. Toothed cams which meshwith one another can be used instead of rope-connected cams or chainscan be employed with toothed cams instead of ropes. f

To enable the steering'movements 'of the iront wheel M to be transmittedto the corresponding rearwheel Q, a pulley M2 on the tubular support M1is connected by crossed belting R to a corresponding pulley Q1 on thetubular support of the rear wheel. Y

Thus it will be seen that Vsteering is directly transmitted to thedriven wheels G, G1 by the worm shaft K controlled bythe steering wheelK3. that the steeringmovement ofthe front wheel G is transmitted throughthe Ycam mechanism to the other front wheel M and the steering movementof the front wheel M is transmitted by the belting R to the back wheelQ.V As a` result the front and rear wheels G, G1, on the same side ofthe chassis are simultaneously driven at the'same speed from a singlepower unit C andeven if owing to slippery or uneven ground the drivecannot be satisfactorily transmittedthrough both wheels simultaneously,atleast one of the driving Wheels G, G1 will always be effective.

The drivers seat L is conveniently mounted to the chassis so as torturnabout a vertical pivot L1. The platform carrying the seat is providedwith two pedals, one of which S enables the clutch to be controlledthrough a flexible power transmission cable whilst the other pedal S1operates a brake T on the vertical shaft D through a similar cable. Thelever U by which the change speed gear is controlled isAk arranged nearthe steering wheel K3 for operation Vby the left-hand of thedriver andthe throttle and other controls (not shown) may be mounted on the end ofthe chassis adjacent to the steeringQwheel.

Obviously instead of an internal combustion engine an electric motordrawing its power from storage batteries suitably housedbelow theplatform may be used and the constructional details may be modified. Forexample, for very heavy loads the trolley may be provided with two ormore axlesat or near each end and instead of a single wheel, a castor orbog'ie assembly may be employed and turn about its supporting Aaxlethrough mechanism of the kind already described.

Should an unlimited turning movement not be required the front drivenwheel may be connected to the undriven wheel on the' opposite side by ay proximately power unit comprises an or link mechanism of a known typethrough the cam and belting illussimple belt instead of trated.

What I claim as my invention and desire to secure by Letters Patent is:

1. A trolley comprising a substantially rectangular chassis or platformsupported at each end upon a pair of steered road wheels, operativeconnections between the road wheels for imparting appropriate steeringmovements to the two wheels at one end of the trolley and in the samedirection and to maintain their axes meeting at apthe centre of turningof the vehicle, similar steering movements in the opposite rotationaldirection to the two wheels at the other end of the trolley, a singlepower unit and a positive driving connection between this unit and thefront and rear wheels on one side only of the trolley such that thesetwo wheels only are driven and at the same speed as one another.

2. A trolley comprising a substantially rectangular chassis or platformsupported at each end upon a pair of steered road wheels, an operativeconnection for imparting the appropriate 'steering movement from a wheelat one end of the trolley to its associated wheel at the same end, anoperative connection between each wheel at one end of the trolley andthe wheel at the other end of the trolley and on the same side thereofsuch that the said two wheels on the same side of the trolley havesimilar steering movements but in the opposite rotational direction, asingle power unit and a positive driving connection between this unitand the front side only of the trolley such that these two wheels onlyare driven and at the same speed.

3. A trolley as claimed in claim 1 in which the power unit comprises aninternal combustion engine including a change-speed gear and clutch,

- a horizontally extending driven shaft positively geared to the roadwheels on one side only of the trolley, and a vertical transmissionshaft connecting the engine-driven shaft through the clutch to thehorizontal driven shaft.

4. A trolley as claimed in claim 2 in which the internal combustionengine including a change-speed gear and clutch, a horizontallyextending driven shaft positively geared to the road wheels on one sideonly of the trolley, and a vertical transmission shaft connecting theengine-driven shaft through the clutch to the horizontal driven shaft.

5. A trolley as claimed in claim 2, wherein the operative connectionbetween the steered wheels includes elliptical cams.

ANTONY SCOTT STOKES.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,621,856 Sedgwick Mar. 22, 19271,369,709 Schuman Feb. 22, 1921 1,382,909 Hennessy et al. June 28, 1921875,893 Buckwalter Jan. 7, 1908 1,255,775 Mueller Feb. 5, 1918 FOREIGNPATENTSr Number Country Date 136,391 Great Britain Dec. 18, 1919 560,112Great Britain Mar. 21, 1944 and rear wheels on one n

